Plant Versus Animal Dietary Protein and the Effect on Proteinuria

The purpose of this study is to investigate if a diet high in protein (2,0 g/kg/d) of plant origin, decreases proteinuria amongst patients with diabetes, hypertension and/or glomerulonephritis with presence of micro- or mild macro albuminuria, compared to a diet high in protein of animal origin.

Kidney insufficiency is associated with increased morbidity and mortality, decreased quality of life and large financial costs for the health care system.

Evidence suggest that the source of protein may inflect the progression of the kidney disease where soy protein has shown a positive effect on estimated glomerular filtration rate and proteinuria amongst both diabetic and non-diabetic patients with nephropathy.

The study design is a 6-week, non-blinded cluster randomized, controlled, cross-over study with two intervention periods of each 14 days. Between interventions there is a washout period of 14 days. The participants are randomized to follow either a diet high in plant protein (HPPD) or a diet high in animal protein (HAPD). The diet plans are individualized to accommodate the participants energy requirements. Given the high amount of protein in the diets they are supplemented with either soy protein powder or beef protein powder. To measure primary and secondary endpoint, the participants are instructed to collect two times 24-hour urine sample at the first baseline, after 14 days and after 42 days. Blood samples are collected at the first baseline, after 14 days, at the second baseline and after 42 days.

To gain enough statistical power a minimum of 16 participants should be included. To accommodate a drop-out rate of 25%, 20 participants should be enrolled.